package cn.tedu.jdbc;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Scanner;

/**
 * 登录功能:
 * 用户输入用户名和密码;
 * 返回结果:
 *   1.登录成功,欢迎您:昵称;
 *   2.用户名或者密码错误;
 * SELECT nickname FROM userinfo WHERE username='' AND password=''
 */
public class JDBCLogin {
    public static void main(String[] args) {
        try (Connection connection = DBUtil.getConnection();){
            //接收用户名和密码
            Scanner scanner = new Scanner(System.in);
            System.out.println("用户名:");
            String username = scanner.nextLine();
            System.out.println("密码:");
            String password = scanner.nextLine();
            //执行SQL
            Statement statement = connection.createStatement();
            //
            String sql = "SELECT nickname FROM userinfo WHERE username='"+username+"' AND password='"+password+"'";
            ResultSet r = statement.executeQuery(sql);
            //判断
            if (r.next()){//登录成功
                String nickname = r.getString("nickname");
                System.out.println("登录成功,欢迎您:" + nickname);
            }else {//登录失败
                System.out.println("用户名或密码错误");
            }
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
    }
}



















